多巴胺用量对Fe3O4@PDA@PAMAM磁性纳米吸附材料的微观结构及吸附性能的影响

Effect of Dopamine Dosages on the Microstructure and Adsorption Properties of the Fe3O4@PDA@PAMAM Magnetic Nano-adsorbed Materials

以自制的Fe3O4磁性纳米材料为核,多巴胺(DA)为表面修饰剂,成功地将2.0 G聚酰胺-胺(PAMAM)树状大分子接枝在Fe3O4磁核表面,制备出了一系列不同DA含量的Fe3O4@PDA@PAMAM磁性纳米吸附材料。采用X射线衍射仪(XRD)、红外光谱仪(IR)、振动样品磁强计(VSM)、透射电子显微镜(TEM)和电感耦合等离子体发射光谱仪(ICP-OES)等分析测试手段对材料组成、微观结构、磁性能和对重金属Cd(Ⅱ)离子的吸附性能进行了测试和表征。研究了修饰剂DA用量对Fe3O4@PDA@PAMAM磁性纳米吸附材料的相组成、微观结构、磁性能和吸附性能的影响。实验结果表明,Fe3O4@PDA@PAMAM磁性纳米吸附材料均呈典型的核-壳结构,材料晶型均呈现尖晶石结构,且壳层厚度随DA用量增加而增厚;材料的饱和磁化强度(Ms)均比Fe3O4的小,且随着DA用量的增加而降低,并且材料的矫顽力(Hc)和剩余磁化强度(Mr)均较低,其磁响应特性适合于做为可回收磁性纳米吸附材料。材料对Cd(Ⅱ)离子的平衡吸附容量随着DA用量的增加呈先增加后减小趋势。当Fe3O4和DA的质量比为8∶4时,吸附剂对Cd(Ⅱ)离子的吸附容量达到最大值165.13 mg·g^-1。

s:A series of the Fe3O4@PDA@PAMAM magnetic nano-adsorbed materials with different dopamine(DA)dosages were prepared by using self-made Fe3O4 as magnetic core materials and DA as surface modifier,then grafting with 2.0 G polyamide-amine(PAMAM)macromolecule.The composition,microstructure,magnetic properties and adsorption properties of heavy metal Cd(Ⅱ)ions were studied by X-ray diffractometer(XRD),infrared spectrometer(IR),vibrating sample magnetometer(VSM),transmission electron microscope(TEM)and inductively coupled plasma emission spectrometer(ICP-OES).The effect of DA dosages on the phase composition,microstructure,magnetic properties and adsorption properties of Fe3O4@PDA@PAMAM magnetic nano-adsorbed materials were researched as well.The results showed that Fe3O4@PDA@PAMAM magnetic nano-adsorbed materials were typical core-shell structure while the thickness of the shell increased with the increase of DA dosages,and the crystal forms of the materials all showed spinel structure.The saturation magnetization(Ms)of Fe3O4@PDA@PAMAM with different DA dosages decreased with the increase of DA dosages,which was smaller than that of Fe3O4.As the coercivity(Hc)and residual magnetization(Mr)of the materials were lower,the magnetic response characteristics of magnetic nano-adsorbed materials showed good recycling performance.The equilibrium adsorption capacity of Fe3O4@PDA@PAMAM magnetic nano-adsorbed materials for Cd(Ⅱ)ions increased firstly and then decreased with the increase of DA dosages.When the mass radio of Fe3O4 and DA was 8∶4,the adsorption capacity of the prepared materials for Cd(Ⅱ)ions has a maximum of 165.13 mg·g-1.